Answers

Add 20/21 and 56/64

20/21 + 56/64 is 307/168.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 64 is 1344
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1344
2. For the 1st fraction, since 21 × 64 = 1344,
   20/21 = 20 × 64/21 × 64 = 1280/1344
3. Likewise, for the 2nd fraction, since 64 × 21 = 1344,
   56/64 = 56 × 21/64 × 21 = 1176/1344
4. Add the two like fractions:
   1280/1344 + 1176/1344 = 1280 + 1176/1344 = 2456/1344
5. 2456/1344 simplified gives 307/168
6. So, 20/21 + 56/64 = 307/168
   In mixed form: 1139/168

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